7Semi SHT40 Temperature & Humidity Sensor Breakout I2C Qwiic SHT40 Breakout

What this sensor is

The 7Semi SHT40 Temperature & Humidity Sensor Breakout (I2C Qwiic) is a high-precision digital environmental sensor used to measure:

• Temperature

• Humidity

It's part of Sensirion's SHT4x series, known for excellent accuracy + ultra-low power

Core Concept (VERY IMPORTANT)

This is a fully digital, factory-calibrated sensor

• No calibration required

• Direct I2C output

• High resolution (16-bit)

Just connect and read values

Key Specifications

• Interface: I2C (Qwiic compatible)

• Resolution: 16-bit

• Temperature Range: -40trong>Humidity Range: 0100% RH

• Humidity Accuracy: 1.5% to 1.8% RH

• Operating Voltage: 3.3V5V (breakout)

• Power Consumption: extremely low (W range)

• Response Time: ~8 seconds

What makes Qwiic special

The Qwiic connector allows:

• Plug-and-play connection

• No soldering

• Daisy-chain multiple sensors

Makes prototyping super easy

Working Principle

• Uses CMOSens technology

• Combines:

  • Capacitive humidity sensing

  • Temperature sensing + processing

   

Outputs ready-to-use digital3V / 5V

GND Ground

SDA Data

SCL Clock

Default I2C address: 0x44

Key Features

• High accuracy (0.2C, 1.8% RH)

• Ultra-low power (battery-friendly)

• Compact & reliable

• Plug-and-play Qwiic system

• Works with Arduino, ESP32, Raspberry Pi

Applications

• Weather stations

• Smart home systems

• Smart agriculture

• Data logging

• HVAC systems

• IoT devices

Important Notes ( will be inaccurate

2. Needs airflow

• Don't seal it inside a box

• Allow air circulation

3. Self-heating (minor)

• Avoid very frequent readings Use interval: 15 seconds

SHT40 vs SHT41

SHT40 vs DHT22

• Reliable IoT sensing

• Low power devices

• High accuracy without complexity

• Easy plug-and-play setup

When NOT to use

Avoid if:

• You need pressure use BME280

• Ultra-high precision use SHT41

Final Understanding

This sensor = professional-grade temperature + humidity sensor (easy to use) One of the best choices for IoT + environmental monitoring

Pro Tip (Very Useful)

Best combo setup:

• SHT40 Temp + Humidity

• ENS160 / SGP40 Air quality

• CO / HCHO sensor